GO:0032299 ribonuclease H2 complex: Components, Assembly and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0032299 (ribonuclease H2 complex) is a cellular component defined as a protein complex with ribonuclease H activity whose catalytic subunit belongs to the RNase H2 (or HII) class.
• In Saccharomyces cerevisiae the complex contains Rnh201p, Rnh202p and Rnh203p, while the human complex is built from RNASEH2A, RNASEH2B and RNASEH2C.
• The complex removes ribonucleotides embedded in DNA-RNA hybrids and helps resolve R-loops, thereby protecting genomic integrity.
• Biallelic mutations in RNase H2 subunits cause Aicardi-Goutieres syndrome, a type I interferonopathy, and clinical non-penetrance has been reported.
• RNase H2 has functions beyond its catalytic activity, including protein-protein interactions and roles in nucleic-acid-mediated inflammation.
• CRISPR knockout, point-mutation, knock-in and overexpression models enable causal dissection of RNase H2 complex biology.
Description
The ribonuclease H2 complex (GO:0032299) is a cellular component defined by its possession of ribonuclease H activity, with a catalytic subunit belonging to the RNase H2 (or HII) class. In the yeast Saccharomyces cerevisiae the complex is composed of Rnh201p, Rnh202p and Rnh203p, and the human counterpart comprises RNASEH2A, RNASEH2B and RNASEH2C. This complex is a major source of ribonuclease H activity in eukaryotic cells and is central to the metabolism of DNA-RNA hybrids. Researchers study GO:0032299 because it safeguards genome stability and because its dysfunction is linked to human inflammatory disease.
ribonuclease H2 complex At A Glance
| GO ID | GO:0032299 |
|---|---|
| GO term | ribonuclease H2 complex |
| Ontology | cellular_component |
| Synonym | RNase H2 complex |
| Major function | Ribonuclease H activity that cleaves RNA in DNA-RNA hybrids |
| Yeast subunits | Rnh201p, Rnh202p and Rnh203p |
| Human subunits | RNASEH2A, RNASEH2B and RNASEH2C |
| Associated disease | Aicardi-Goutieres syndrome and related interferonopathies |
| Related process | R-loop processing and genomic integrity |
What Is GO:0032299?
According to the Gene Ontology, GO:0032299 (ribonuclease H2 complex) is a protein complex that possesses ribonuclease H activity, in which the catalytic subunit is a member of the RNase H2 (or HII) class. The term is a cellular component, meaning it describes a location and assembly of proteins rather than a process or a molecular function. In Saccharomyces the complex contains Rnh201p, Rnh202p and Rnh203p, and the human complex contains RNASEH2A, RNASEH2B and RNASEH2C. The synonym RNase H2 complex is used interchangeably with the official name.
Why Is ribonuclease H2 complex Important in Cell Biology?
GO:0032299 is important because the ribonuclease H2 complex is a principal enzyme for removing ribonucleotides from DNA and for processing R-loops, thereby maintaining genomic integrity. Its dysfunction causes Aicardi-Goutieres syndrome, a type I interferonopathy, and contributes to nucleic-acid-mediated inflammatory disease. Because the complex also has non-catalytic roles, it is a model for studying how protein complexes coordinate nucleic-acid metabolism and innate immune signaling.
• Maintains genomic integrity by removing ribonucleotides embedded in DNA.
• Processes R-loops in cooperation with other complexes such as Smc5/6.
• Mutations in RNase H2 subunits cause Aicardi-Goutieres syndrome.
• Links nucleic-acid metabolism to type I interferon-mediated inflammation.
• Has functions beyond its enzyme activity, including protein interactions.
• Is conserved from yeast to humans, enabling model-organism studies.
• Is relevant to antigenic variation in Trypanosoma brucei.
• Provides a target for understanding ribonucleotide excision repair.
• Serves as a paradigm for multi-subunit nuclease complexes.
• Supports research on autoinflammatory and autoimmune disease mechanisms.
Structure and Composition of ribonuclease H2 complex
Subunit composition
In simple terms: The complex is built from three different proteins that work together.
In Saccharomyces cerevisiae the ribonuclease H2 complex contains Rnh201p, Rnh202p and Rnh203p, and in humans the complex contains RNASEH2A, RNASEH2B and RNASEH2C. The catalytic subunit is a member of the RNase H2 (or HII) class, which defines the complex.
Catalytic subunit
In simple terms: One subunit does the cutting of RNA in DNA-RNA hybrids.
The catalytic subunit of the complex belongs to the RNase H2 class and provides the ribonuclease H activity that defines GO:0032299. This activity cleaves the RNA strand of DNA-RNA hybrids.
Accessory subunits
In simple terms: The other subunits help the enzyme work and interact with partners.
The non-catalytic subunits Rnh202p and Rnh203p in yeast, and RNASEH2B and RNASEH2C in humans, are essential components of the complex. They contribute to complex stability and to functions beyond catalysis, as the role of human RNase H2 may not be restricted to its enzyme activity.
Conservation and assembly
In simple terms: The same three-part design is found from yeast to humans.
The ribonuclease H2 complex is conserved across eukaryotes, with orthologous subunits in yeast and humans. Assembly of the three subunits is required for the complex to carry out its roles in nucleic-acid metabolism.
Interaction with other complexes
In simple terms: The complex cooperates with other machines in the cell.
The Smc5/6 complex counteracts R-loop formation at highly transcribed genes in cooperation with RNase H2. In Trypanosoma brucei, a DOT1B/ribonuclease H2 protein complex is involved in R-loop processing, genomic integrity and antigenic variation.
Key Genes Involved in GO:0032299 ribonuclease H2 complex
The following genes and proteins are the principal components and interactors of the ribonuclease H2 complex (GO:0032299) as reported in the cited literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| RNASEH2A | Catalytic subunit of human RNase H2 complex | Mutations linked to Aicardi-Goutieres syndrome |
| RNASEH2B | Accessory subunit of human RNase H2 complex | Mutations linked to Aicardi-Goutieres syndrome |
| RNASEH2C | Accessory subunit of human RNase H2 complex | Mutations linked to Aicardi-Goutieres syndrome |
| Rnh201p | Catalytic subunit in Saccharomyces cerevisiae | Yeast model for RNase H2 function |
| Rnh202p | Accessory subunit in Saccharomyces cerevisiae | Yeast model for complex assembly |
| Rnh203p | Accessory subunit in Saccharomyces cerevisiae | Yeast model for complex assembly |
| DOT1B | Partners with ribonuclease H2 in Trypanosoma brucei | R-loop processing and antigenic variation |
| SMC5 | Component of Smc5/6 complex cooperating with RNase H2 | R-loop suppression at transcribed genes |
| SMC6 | Component of Smc5/6 complex cooperating with RNase H2 | R-loop suppression at transcribed genes |
| RNASEH1 | Related ribonuclease H enzyme in eukaryotes | Comparative studies of RNase H family |
| RNASEH2A orthologs | Catalytic subunit across eukaryotes | Evolutionary and functional studies |
| RNASEH2B orthologs | Accessory subunit across eukaryotes | Evolutionary and functional studies |
| RNASEH2C orthologs | Accessory subunit across eukaryotes | Evolutionary and functional studies |
| Interferon-stimulated genes | Downstream of nucleic-acid sensing in AGS | Inflammation research |
| cGAS-STING pathway components | Nucleic-acid-mediated inflammatory signaling | Innate immunity research |
| ADAR1 | Related nucleic-acid editing enzyme in interferonopathies | Comparative disease studies |
| TREX1 | Related exonuclease in Aicardi-Goutieres syndrome | Comparative disease studies |
How Is ribonuclease H2 complex Regulated?
The ribonuclease H2 complex is regulated at the level of subunit expression and assembly, and its activity is coordinated with other genome-maintenance complexes. The Smc5/6 complex cooperates with RNase H2 to counteract R-loop formation at highly transcribed genes, indicating that RNase H2 function is integrated with chromatin-associated processes. In Trypanosoma brucei, a DOT1B/ribonuclease H2 complex is involved in R-loop processing and antigenic variation, showing that the complex can be recruited to specific genomic contexts. The role of human RNase H2 may not be restricted to its enzyme activity, suggesting additional regulatory interactions.
ribonuclease H2 complex and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| RNASEH2A | Aicardi-Goutieres syndrome | Knockout and point-mutation cell models |
| RNASEH2B | Aicardi-Goutieres syndrome | Knockout and point-mutation cell models |
| RNASEH2C | Aicardi-Goutieres syndrome | Knockout and point-mutation cell models |
| RNASEH2A/B/C | Nucleic-acid-mediated inflammation | Reporter and interferon-stimulation assays |
| RNASEH2A/B/C | R-loop-associated genomic instability | R-loop detection and genome-integrity assays |
Aicardi-Goutieres syndrome
Biallelic mutations in the RNase H2 complex subunits cause Aicardi-Goutieres syndrome, a type I interferonopathy. Clinical non-penetrance associated with biallelic mutations in the RNase H2 complex has been reported, indicating variable expressivity. The syndrome is characterized by nucleic-acid-mediated inflammatory disease.
Nucleic-acid-mediated inflammatory disease
Defects in the ribonuclease H2 complex lead to accumulation of nucleic-acid species that trigger innate immune sensing and type I interferon responses. This links GO:0032299 to inflammatory diseases beyond Aicardi-Goutieres syndrome.
Genomic instability and R-loop-associated stress
The ribonuclease H2 complex processes R-loops and maintains genomic integrity, and its cooperation with Smc5/6 is important at highly transcribed genes. Loss of this function can contribute to genome instability.
From ribonuclease H2 complex-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| What is the catalytic contribution of RNASEH2A? | Point-mutation knock-in of catalytic residues |
| How does loss of RNase H2 affect R-loops? | Knockout cell lines with R-loop detection |
| Does a disease-associated variant alter complex assembly? | Knock-in of patient variants |
| Where is the complex localized? | Tagged knock-in for imaging |
| Does overexpression change interferon signaling? | Overexpression cell models |
| Which genes cooperate with RNase H2? | CRISPR library screening |
How to Study the ribonuclease H2 complex Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Transcriptome changes after perturbation | Pathway analysis of RNase H2 loss |
| R-loop detection | R-loop accumulation | Genomic integrity studies |
| Proteomics | Protein interactions and complex composition | Identification of partners |
| Interferon reporter assays | Type I interferon signaling | Inflammation studies |
| Genome instability assays | DNA damage and instability | R-loop-associated stress |
| Imaging of tagged subunits | Subcellular localization | Complex assembly studies |
| CRISPR screening | Genetic dependencies and modifiers | Pathway discovery |
| Yeast genetics | Conserved complex function | Model-organism studies |
Genomic and transcriptomic methods
RNA-seq and related transcriptomic approaches can measure gene expression changes after perturbation of the ribonuclease H2 complex. These methods help link complex loss to downstream inflammatory and genome-maintenance pathways.
R-loop detection
R-loop detection assays are used to study how the ribonuclease H2 complex and its partners, such as Smc5/6, counteract R-loop formation at highly transcribed genes. Such assays are central to understanding the genomic integrity functions of GO:0032299.
Protein interaction and proteomics
Proteomic and interaction studies can identify partners of the ribonuclease H2 complex, including DOT1B in Trypanosoma brucei and Smc5/6 components. These approaches help define functions beyond the catalytic activity of the complex.
Inflammation and interferon assays
Interferon-stimulation and nucleic-acid-sensing assays are used to study the inflammatory consequences of ribonuclease H2 complex dysfunction. They connect GO:0032299 to Aicardi-Goutieres syndrome and related interferonopathies.
How CRISPR Can Be Used to Study GO:0032299 ribonuclease H2 complex
Knockout
CRISPR knockout of RNASEH2A, RNASEH2B or RNASEH2C can eliminate ribonuclease H2 complex activity and reveal its roles in R-loop processing and genomic integrity. Knockout models are also used to study inflammatory consequences of complex loss.
Point Mutation
Point-mutation knock-in can model disease-associated variants in the RNase H2 complex and test whether catalytic or assembly functions are affected. Such models help dissect the non-catalytic roles of human RNase H2.
Knock-in
Knock-in of tagged subunits allows visualization and purification of the ribonuclease H2 complex for interaction and localization studies. Knock-in of patient variants supports genotype-phenotype studies.
Overexpression
Overexpression of RNase H2 subunits can test whether increased complex levels alter nucleic-acid metabolism or interferon signaling. These models complement loss-of-function studies.
How EDITGENE Supports ribonuclease H2 complex Research
Researchers studying ribonuclease H2 complex-related genes often need to determine whether a candidate gene is causally involved in R-loop processing, genomic integrity or inflammatory signaling, and CRISPR-based models provide a direct way to test this.
Contact EDITGENE today to design your custom CRISPR model for ribonuclease H2 complex research.
Frequently Asked Questions About ribonuclease H2 complex
What is the ribonuclease H2 complex?
It is a protein complex with ribonuclease H activity whose catalytic subunit belongs to the RNase H2 class, defined as GO:0032299.
What genes are involved in the ribonuclease H2 complex?
In humans the complex contains RNASEH2A, RNASEH2B and RNASEH2C, and in yeast it contains Rnh201p, Rnh202p and Rnh203p.
What does GO:0032299 mean?
GO:0032299 is the Gene Ontology cellular component term for the ribonuclease H2 complex.
What is the function of RNase H2?
It cleaves RNA in DNA-RNA hybrids and helps process R-loops, maintaining genomic integrity.
Which diseases are linked to the ribonuclease H2 complex?
Biallelic mutations in its subunits cause Aicardi-Goutieres syndrome, a type I interferonopathy.
Is the ribonuclease H2 complex conserved?
Yes, orthologous subunits are found from yeast to humans.
Does RNase H2 have functions beyond its enzyme activity?
Yes, the role of human RNase H2 may not be restricted to its enzyme activity.
How is the ribonuclease H2 complex studied?
Common methods include knockout and knock-in models, R-loop detection, proteomics and interferon assays.
What is Aicardi-Goutieres syndrome?
It is an inflammatory disease associated with mutations in nucleic-acid-metabolizing enzymes including the RNase H2 complex.
Can CRISPR be used to study the ribonuclease H2 complex?
Yes, CRISPR knockout, point-mutation, knock-in and overexpression models are used to dissect its functions.
Conclusion
GO:0032299 (ribonuclease H2 complex) is a conserved cellular component that removes ribonucleotides from DNA and processes R-loops, thereby protecting genomic integrity. Its dysfunction is linked to Aicardi-Goutieres syndrome and nucleic-acid-mediated inflammation, and its roles extend beyond catalysis. CRISPR-based models and related methods provide powerful tools to study this complex and its disease relevance.
References
- 1. Eisenhuth N et al.. 2021. A DOT1B/Ribonuclease H2 Protein Complex Is Involved in R-Loop Processing, Genomic Integrity, and Antigenic Variation in Trypanosoma brucei.. mBio 12(6):e0135221 PMID: 34749530
- 2. Roy S et al.. 2024. The Smc5/6 complex counteracts R-loop formation at highly transcribed genes in cooperation with RNase H2.. Elife 13 PMID: 39404251
- 3. Stephenson JB. 2008. Aicardi-Goutières syndrome (AGS).. Eur J Paediatr Neurol 12(5):355-8 PMID: 18343173
- 4. Reijns MA et al.. 2014. Ribonuclease H2 in health and disease.. Biochem Soc Trans 42(4):717-25 PMID: 25109948
- 5. Rigby RE et al.. 2008. Nucleic acid-mediated inflammatory diseases.. Bioessays 30(9):833-42 PMID: 18693262
- 6. Feng S et al.. 2016. Is the role of human RNase H2 restricted to its enzyme activity?. Prog Biophys Mol Biol 121(1):66-73 PMID: 26603688
- 7. Crow YJ et al.. 2023. Clinical Non-penetrance Associated with Biallelic Mutations in the RNase H2 Complex.. J Clin Immunol 43(4):706-708 PMID: 36705819
- 8. Cerritelli SM et al.. 2009. Ribonuclease H: the enzymes in eukaryotes.. FEBS J 276(6):1494-505 PMID: 19228196
